FXHW60 PHFO 250137
AFDHFO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
400 PM HST THU DEC 24 2009
.SYNOPSIS...
A COLD FRONT OVER KAUAI WILL ADVANCE TO MAUI COUNTY THROUGH
CHRISTMAS DAY THEN SLOWLY DISSIPATE...BRINGING SOME SHOWERS. HIGH
PRESSURE PASSING NORTH OF THE ISLANDS BEHIND THE FRONT WILL BRING
LIGHT TO MODERATE TRADES BRIEFLY CHRISTMAS DAY AND SATURDAY. WIND
WILL BECOME LIGHT AND VARIABLE WITH LAND AND SEA BREEZES NEXT WEEK
AS A HIGH PRESSURE RIDGE IS EXPECTED TO MOVE NEAR THE ISLANDS.
&&
.DISCUSSION...
CLOUD BAND ASSOCIATED WITH THE FRONT HAS ADVANCED TO THE NORTHERN
PORTION OF OAHU THIS AFTERNOON...WITH THE MAIN FRONTAL BAND OVER
KAUAI. LIHUE REPORTED THE WIND SHIFT BY NOON...WITH THE NORTHERLY
WINDS INCREASED QUITE A BIT IN THE AFTERNOON. RAINFALL AMOUNTS
REPORTED AROUND KAUAI ARE RESPECTABLE...WITH HIGHEST READING AT
WAINIHA TOTALING ALMOST ONE AND A QUARTER INCH OF RAIN SO FAR.
EXPECT SOME MORE SHOWERS TO AFFECT KAUAI THROUGH REST OF THIS
AFTERNOON INTO THE EVENING...WITH SOME CLEARING OVERNIGHT. OAHU
WILL SEE AN INCREASE IN CLOUDS AND SHOWERS IN THE COMING HOURS...AND
STAY CLOUDY OVERNIGHT BEFORE SOME CLEARING BY EARLY CHRISTMAS DAY.
THIS FRONT WILL REACH MAUI COUNTY BY CHRISTMAS DAY...THEN IT IS
EXPECTED TO STALL AND DISSIPATE IN THE VICINITY. THAT IS AS MUCH
WEATHER AS THIS SYSTEM WILL BRING TO THE ISLANDS...AS THE MAIN UPPER
LEVEL TROUGH STAYS PRETTY MUCH NORTH OF LATITUDE 30N. REMNANT
MOISTURE FROM THE DISSIPATED FRONT WILL CONTINUE TO BRING SOME
CLOUDS AND SHOWERS TO THE NORTHERN ISLANDS. LOOKS LIKE BIG ISLAND
MAY BE SPARED...THOUGH IT IS POSSIBLE SOME OF THE MOISTURE MAY REACH
THAT FAR SOUTH LATER CHRISTMAS DAY INTO SATURDAY.
TRADES WILL INCREASE BRIEFLY BEHIND THE FRONT ON CHRISTMAS DAY AND
EARLY SATURDAY AS HIGH PRESSURE PASSES THE NORTH OF THE STATE. WINDS
ARE FORECAST TO TURN SOUTHEASTERLY BY SATURDAY NIGHT AS A RIDGE
MOVES NEAR THE ISLANDS ONCE AGAIN...AHEAD OF ANOTHER APPROACHING
FRONT THE NORTHWEST. LATEST FORECAST CHARTS STILL INDICATE THIS NEXT
FRONT WILL STAY NORTH OF THE ISLANDS...WHILE THE HIGH PRESSURE RIDGE
WILL REMAIN NEAR THE ISLANDS. DUE TO THE CLOSE PROXIMITY OF THE
RIDGE...WINDS WILL BE LIGHT...ALLOWING LAND AND SEA BREEZES TO
DEVELOP. THIS RIDGE IS EXPECTED TO HOVER NEAR THE ISLANDS AT LEAST
THROUGH FIRST HALF OF NEXT WEEK. FORECAST CHARTS INDICATE AIR MASS
WILL REMAIN MARGINALLY STABLE...WITH NO ORGANIZED MOISTURE EXPECTED.
LOOK FOR THE RETURN OF CONVECTIVE TYPE WEATHER REGIME OVER THE
ISLANDS...WITH CLOUDS AND SHOWERS DEVELOPING OVER THE ISLANDS DURING
THE DAY TIME AND CLEARING AT NIGHT. PRECIPITATION SHOULD BE LIMITED
UNDER THE NOT TOO FAVORABLE CONDITIONS. THE SMALLER ISLANDS MAY SEE
A RETURN OF VOLCANIC EMISSIONS FROM THE BIG ISLAND AS WINDS TURN
LIGHT SOUTHEASTERLY AT TIMES.
&&
.MARINE...
LATEST READINGS FROM BUOYS NORTHWEST OF THE ISLANDS ARE WAY UP THIS
AFTERNOON. THE VERY LARGE NORTHWEST SWELL WILL REACH KAUAI LATER
THIS AFTERNOON INTO THE EVENING. EXPECT THE SURF WILL BUILD
RAPIDLY IN THE COMING HOURS ALONG NORTH AND WEST FACING SHORES OF
NIIHAU AND KAUAI TO WARNING LEVELS...THEN SPREADING TO THE REST OF
THE ISLAND CHAIN THROUGH CHRISTMAS DAY. HIGH SURF WARNING IS IN
EFFECT UNTIL SATURDAY FOR NORTH AND WEST FACING SHORES OF THE
NORTHERN ISLANDS. SURF HEIGHTS OF NORTH AND WEST FACING SHORES OF
THE NORTHERN ISLANDS WILL LOWER TO ADVISORY LEVELS LATER SATURDAY
AND BRIEFLY TO BELOW ADVISORY LEVELS ON SUNDAY. A NEW NORTHWEST
SWELL BY MONDAY IS EXPECTED BRING ADVISORY LEVEL SURF ONCE AGAIN.
&&
.HFO WATCHES/WARNINGS/ADVISORIES...
HIGH SURF WARNING UNTIL 6 PM HST SATURDAY FOR NIIHAU-KAUAI
WINDWARD-KAUAI LEEWARD-WAIANAE COAST-OAHU NORTH
SHORE-OAHU KOOLAU-MOLOKAI-MAUI WINDWARD WEST-MAUI CENTRAL VALLEY-
WINDWARD HALEAKALA.
SMALL CRAFT ADVISORY UNTIL 6 PM HST SATURDAY FOR KAUAI NORTHWEST
WATERS-KAUAI WINDWARD WATERS-KAUAI LEEWARD WATERS-KAUAI CHANNEL-
OAHU WINDWARD WATERS-OAHU LEEWARD WATERS-KAIWI CHANNEL-MAUI
COUNTY WINDWARD WATERS-MAUI COUNTY LEEWARD WATERS-ALENUIHAHA
CHANNEL-BIG ISLAND WINDWARD WATERS-BIG ISLAND LEEWARD WATERS-BIG
ISLAND SOUTHEAST WATERS.
&&
$$
HUI
